My new bike (about 1 month) has developed a 'noise' , i think in the freehub. If I spin the bck wheel forward, there's a cyclical noise like something rubbing; if backward or backspinning the cranks it's there again with about the same frequency only quite a bit louder. Could this be in the freehub, or just hub bearings needing adjustment, or ?? Any thoughts welcome. Cheers. (hub is Shim 475 disc).